Finding the Fourth Proportional to 2,255.07, 3,111.30 and 1,260.21

Step by Step Solution

1. Step 1: Write the proportion equation
   2,255.07 : 3,111.30 = 1,260.21 : x
2. Step 2: Convert to fraction form
   2,255.07/3,111.30 = 1,260.21/x
3. Step 3: Cross multiply
   2,255.07x = 3,111.30 × 1,260.21
4. Step 4: Simplify right side
   2,255.07x = 3,920,891.37
5. Step 5: Solve for x
   x = 3,920,891.37/2,255.07
6. Step 6: Final answer
   x = 1,738.70